Abstracts

INSECTICIDE RESISTANCE IN MOSQUITOES: POSSIBLE APPROACHES FOR ITS MANAGEMENT A. P. Dash Director National Institute of Malaria Research 22- Sham Nath Marg, Delhi – 54 [email protected]

By the end of 19 th century, many discoveries were made especially on the transmission of diseases by insect vectors. Among the different insect vectors species, mosquitoes were responsible for many diseases causing sever morbidity and mortality. Since, effective drugs and preventive vaccines were not available the focus of disease control depended on vector control. Initially the control efforts were by non-chemical methods to control breeding of mosquitoes with physical methods to stop mosquito bites and disease transmission. Discovery of DDT in 1940’s was the major breakthrough for the control of vector borne diseases by indoor residual sprays. Success witnessed was short-lived mainly due to the development of widespread resistance to DDT and to other insecticides of different groups. The situation of vector borne diseases further deteriorated in the later years compounded by various factors including drug resistance, improved receptivity due to various developmental activity, migration, etc. More than 90% of vector borne diseases are transmitted by mosquitoes. World over more than 3,000 species of mosquitoes under 38 genera and in India 255 species under 15 genera are reported so far. The four major mosquito genera responsible for diseases transmission in the world are Anopheles (422 species: 65-70 vector species), Aedes (888 species and 25), Culex (715 and 12) and Mansonia (23 and 7). In India the prevalence in Anopheles (58 species: 6 major vectors), Aedes (111species: 2 vectors), Culex (57 species: 3 vector species) and Mansonia (4 species: 1 vector species). The major diseases transmitted include malaria followed by lymphatic filariasis, dengue and Japanese Encephalitis including the recent out break of chikungunya fever in different states in the country. The global estimate of malaria is 300 to 500 million each year with deaths ranging from 1.5 to 2.7 million each year. These include mostly children from Sub-Saharan region, south of Africa. In South-East Asia region India contributes 77% of the total cases 2.4 million in the region. In India, 4 states [Orissa (24%), Chhattisgarh(14%), West Bengal (10%), Madhya Pradesh (8%) and (North East states (9%)] and North eastern states contributes 65% of total cases of malaria. Eighty countries in South-East Asia region are reported endemic for Lymphatic Filariasis including India. India contributes to more than 40% of the global filariasis 1

cases. About 50,000 cases of Japanese Encephalitis are reported annually from SouthEast Asia and Western Pacific region with 15,000 deaths. Recurrent outbreaks of Japanese Encephalitis are reported fron the states of Andhra Pradesh, Uttar Pradesh and other states. This year by November 2006, 65 deaths were reported due to dengue alone in Delhi. The other states that have reported dengue cases are Kerala, Rajasthan, Gujarat, West Bengal, Uttar Pradesh, Tamil Nadu, Punjab, Maharashtra, Haryana, Karnataka and Andhra Pradesh. In the year 2006, several states in India have been simultaneously hit by chikungunya outbreaks leading to occurrence of more than 1.37 million clinically suspected cases from 188 districts in 12 states and Union Territories. The affected states are Andhra Pradesh, Andaman & Nicobar Islands, Tamil Nadu, Karnataka, Maharashtra, Gujarat, Madhya Pradesh, Kerala & Delhi. The largest number of cases has been reported by Karnataka (752,245) followed by Maharashtra (258,998). The disease carries a high attack rate which was observed to be up to 45% in some areas. As is the case Globally, .in India also vector control mainly relies on the application of chemical insecticides for larviciding, indoor residual spray and other interventions. Most of the insect vectors of diseases are mostly susceptible to different insecticides except malaria vectors. Among the six principle vectors of malaria, An. culicifacies is solely responsible for transmitting 65% of the malaria cases annually. This species is also a complex of sibling species showing differential biological characters that have a bearing on the epidemiology of malaria and are multiple resistant to DDT, malathion and synthetic pyrethroids in some foci. The development of resistance in An. culicifacies was also found due to selection by pesticides being sprayed in agriculture on cash crops and rendering insecticides of certain groups ineffective. In the present scenario of wide spread resistance in the vectors, the option left for vector control is management of resistance in the vectors by employing suitable strategies to delay the onset of resistance or manage at such a level where the disease transmission could be contained. This is possible by different suggested methods for management but rotation of insecticides belonging to unrelated groups has shown promise. In order to sustain vector control an effective multi-tactic integrated vector control programme should be developed. This requires pro-active approach integrating judicious and optimal use of chemical insecticides coupled with biological control and environmental management methods.

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CAN WE WIN OVER THE MOSQUITO IN NEAR FUTURE? P. Umamahaeshwara Reddy Professor of Zoology Dean, Development & UGC Affairs, Osmania University, Hyderabad - 7.

Mosquito borne problems to human beings are known from ages immemorial. Soon after the discovery of DDT till late seventies, mosquito borne diseases had decreased drastically due to the application of DDT which was familiarly renowned as “magic bullet”. In due course of time some mosquito species become resistant due to indiscriminate usage of DDT. Subsequently, mosquito control methods were switched over to many organophosphate insecticides like Malathion, Fenthion, Chlorpyrifos, Permethrin, Deltamethrin and Resmethrin, etc., which reserved their quota of millions of rupees in every five-year plan, till these were ineffective to win over the mosquitoes. By the time laboratory-tested methods comes to application-side in the field it witnesses its ineffectiveness for which reasons are many. One among these is improper management that lead to the development of resistance in mosquitoes. Imprudent land use pattern in the name of civilization, urbanization and industrialization is another setback in tackling mosquito menace. These artificial habitats turned into conducive ambiances for mosquito breeding wherein they wouldn’t find any natural predators, thereby mosquito population exceeds beyond the tolerable limits. The consequences have resulted in many mosquito borne diseases such as Malaria, Filariasis, Dengue, Chikungunya and Japanese encephalitis and many more may be lurking for their turn due to our own ignorance and lack of information. There is no sector in India that is not affected by mosquitoes. Very recently Chikungunya and Dengue have devastated visible effect on day-to-day earnings of the common man, which also reflects on gross domestic product of the nation, and thereby its all-round development. India’s inherent vulnerabilities can’t be ruled out due to lack of methodical town planning and sanitary disposal and stringent municipal enforcement, which ultimately leads to mosquito multiplication. As the saying goes, “In the chilled winter-night a dog thinks to acquire a blanket but forgets it in the day….”. Individually, every one thinks that mosquitoes are not worth bothering. Particularly in urban areas, people with different cultures, customs and dogmas lack uniform civic sense. Hardly anybody owns the responsibility to keep off their own property from mosquitoes breeding, and expects the Government to come to the rescue in controlling mosquito menace. But ultimately someone has to act; who is none other than again the Government that represents the individuals. Unlike concentrating research in unicameral direction, that may not fulfill the objectives in eradication of mosquito borne problems. At this juncture, a rethinking on present mosquito control methodologies is necessary for concerted efforts to tackle the tiny enemy.

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“EFFECT OF GLOBALIZATION AND NATURAL CALAMITIES ON VECTOR BORNE DISEASES” U. Suryanarayana Murty Scientist F/Deputy Director Head Biology Division Indian Institute of Chemical Technology (CSIR), Hyderabad 500007. [email protected]

Globalization is causing profound and complex changes in the very nature of our society, bringing new opportunities as well as risks Despite some empirical research efforts indicating the links between the globalization process and specific health impacts, the present weakness in empirical evidence on the multiple links between globalization and health is still a problem. As transborder mobility of humans, animals, food, and feed products increases, so does the threat of the spread of dangerous pathogens and vector borne disease. Due to globalization, movement of people from one country to another is inevitable where strict surveillance is required to see that the travelers from endemic countries are free from the pathogen otherwise it may lead to spread the disease in non endemic areas. The global proliferation of technology and information has the potential to improve the identification, surveillance, containment, and treatment of vector borne diseases in both developed and developing countries. Growing international cooperation may lead to more robust and transparent reporting regarding disease outbreaks and control efforts. Apart from the globalization natural calamities will have significant role in promoting the vector borne diseases and its outbreak. The World Health Organization (WHO) warned about increased risk of vector-borne diseases such as malaria and dengue fever across tsunami-affected areas in South-East Asia. Nearly four weeks after the disaster struck the region on 26 December, the organizations strengthening its disease surveillance, stagnant water conditions, creating conditions for mosquito vectors to multiply to sufficient levels, to potentially cause severe public health problems. Most affected countries in the region are endemic for dengue fever and malaria except the Maldives, which has no malaria cases but does have dengue cases. With the onset of the rainy season, particularly in Indonesia and Sri Lanka, a rise in the cases can be expected at this time of the year. Indonesia suffered a major dengue outbreak last year. This year too, many cases have been reported in Jakarta, since December and the national authorities have installed control measures for these.

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However, given the extent of destruction due to the tsunami, WHO and the Ministry of Health are concerned about the increased risk of Dengue in Aceh and are carefully monitoring the situation Concerns for malaria remain high, too. Although there is no information to suggest an increase in malaria cases in Banda Aceh, the area is endemic for the disease. “At present, we are dealing with a lot of unknowns because of the violent environmental changes that have taken place here,” explained Dr Jack Chow, Assistant Director-General responsible for malaria at WHO Headquarters Experts have been deployed and an Early Warning and surveillance systems has been established in affected regions. Steps taken to control the vector borne diseases due to natural calamities and globalization are discussed.

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CAUSES AND CONSEQUENCES OF DRUG & INSECTICIDE RESISTANANCE D. T. Naik, I P S Addl. Director General of Police Drug Control & Administration, Govt. of A. P.

Drug resistance of Malarial parasites leads to kill more people today than three decades ago. The disease burden from multi-drug resistant strains of malaria, tuberculosis, hepatitis, and HIV is growing in both developed and developing countries. Treatment failures also lead to longer periods of infection, which increase the numbers of infected people moving in the community and thus expose the general population to the risk of contracting a resistant strain of infection. When infections become resistant to first-line antimicrobials, treatment has to be switched to second- or third-line drugs, which are nearly always much more expensive and sometimes more toxic as well, e.g. the drugs needed to treat multidrug-resistant forms of tuberculosis are over 100 times more expensive than the first-line drugs used to treat non-resistant forms. In many countries, the high cost of such replacement drugs is prohibitive, with the result that some diseases can no longer be treated in areas where resistance to first-line drugs is widespread. Drug resistance is increasing rapidly, largely due to widespread uncontrolled and unregulated drug distribution. Drugs have been used till resistance has rendered them ineffective, after which closely related drugs that are introduced show reduced efficacy and severely compromised life spans. Another underlying factor contributing to the development of resistance is the improper usage of the drugs; for example, subcurative doses - people feel better, so they stop taking their medicine, and some resistant parasites may be given the chance to survive and be transmitted by mosquitoes. Most alarming of all are diseases where resistance is developing for virtually all currently available drugs due to imprudent drug management or may be lack of awareness; current trends suggest some diseases will have no effective therapies within the next ten years. The ever-increasing resistance of disease vectors to biological and chemical pesticides looms as a complicating factor in efforts to control and eliminate the emergence of infectious diseases. Resistance to insecticides has appeared in the major insect vectors from every genus (e.g., mosquitoes, sand flies, ticks, fleas, and lice). Resistance has developed to every chemical class of insecticide, including microbial pesticides and insect growth regulators. Insecticide resistance is predicted to have an increasing and profound affect on the

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reemergence of most vector-borne diseases. And where resistance has not contributed to disease emergence, it is expected to threaten disease control. Insecticide programmes have also been hampered by the emergence of resistance to DDT and other insecticides. Malaria control programs that already face complex challenges presented by multi-drug resistant strains of the disease. Resistance is a natural response of microbes and other organisms to selective pressure from antimicrobial and other biological and chemical countermeasures. Adaptive mechanisms in the organisms permit survival and the development of genetic resistance. While the emergence of resistance cannot be eliminated, the rate and extent of its occurrence can be contained. In order to contain the threats posed to human health by resistance, it is important to determine the magnitude and trends of resistance and to define the relative importance of different contributing factors, such as therapeutic, behavioral, economic and social, and health systems factors, as well as agricultural misuse. Therefore, as saying goes “prevention is better than cure/control” based on this understanding it may be possible to develop effective methods of source reduction to countercheck the resistance in different settings.

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AEDES ALBOPICTUS (SKUSE): THE DEADLY VECTOR OF DENGUE AND OTHER VIRUS INFECTIONS – ITS ECOLOGY AND DIVERSITY IN KERALA STATE, SOUTH INDIA B.K. Tyagi Director Centre for Research in Medical Entomology (ICMR) 4-Sarojini Street, Chinna Chokkikulam, Madurai 625 002 (TN), India. E-mail: [email protected]

Aedes albopictus (Skuse) is a serious vector mosquito of great public health importance. A native of India, where it was first described from Bengal, it is best known as the Asian Tiger mosquito for its not only specific body colour pattern but also its highly attacking and dominating behaviour. All over the world, Ae. albopictus is responsible for over two dozen viral infections, including the deadly dengue in India and the more debilitating chikungunya elsewhere in the Indian ocean. As far as India is concerned, this mosquito has recently emerged as a serious pest and vector, transmitting so far solely the dengue infection in Kerala, even in the presence of Aedes aegypti, the primary and major vector for both dengue and chikungunya. In Kerala, the God’s own Land, rightly referred to as the Venice of India, has during past four decades undergone catastrophic vicissitudes both in its ecology and physiography, in context with rainfall deficiency, forest denudation, changing crop patterns, rise in ambient temperature, unplanned urbanization, depleting water resources and storage habits. The changed ecological scenario in Kerala, supporting dissemination of Ae. albopictus and anthropophagic initiative, is largely credited with the triggering of dengue onset in the State. Dengue epidemics, often associated with deaths, began to occur since 1997 and climaxed in 2003 with 3546 cases (>253-fold increase) and 68 deaths (17-fold increase). A large number of cases and some deaths continue to occur every year since then. Interestingly, Ae. aegypti prevalent insignificantly (4.4%) mostly along the coastal belt could never be incriminated in Kerala. On the contrary, amongst all the 26 species sampled, Ae. albopictus (69.7%) dominated all the possible breeding domains including both the rural environment in sylvatic, mountainous highland zone and the urban coastal lowland coastal areas. Ae. albopictus exhibits great adaptability potential to breed in a large variety of natural and artificial breeding sites, particularly the latex collecting cups along the rubber plantation, besides those of cocoa and coconut. We at the CRME, Madurai have demonstrated detection and isolation of the dengue viruses from Ae. albopictus in nature, besides the phenomenon of transovarial transmission, even in the absence of Ae. aegypti, alluding the former species’ great epidemiological significance in disease transmission. This presentation highlights the vast potential of Ae. albopictus in transmitting dengue in Kerala and other similar ecosystems in the country where its ecology and biodiversity are still not appreciably comprehended. 8

EPIDEMIOLOGICAL PROFILE OF JAPANESE ENCEPHALITIS VIRUS TRANSMISSION IN INDIA N. Arunachalam, P. Philip Samuel, R. Paramasivam, V. Thenmozhi, A. Balasubramanian & B. K. Tyagi Centre for Research in Medical Entomology (ICMR) 4, Sarojini Street, Chinna Chokkikulam Madurai – 625 002, Tamil Nadu, India

Japanese encephalitis (JE) is a mosquito-borne flaviviral disease caused by Japanese encephalitis virus (JEV), and outbreaks occur frequently in Asian countries and about 3060 million people live at risk of infection. JE is a disease of major public health concern due to its high epidemic potential, high case fatality and neuropsychiatric sequelae among survivors. The great majority of cases and deaths occur in South East Asia and Western Pacific. The estimated global burden of JE was 709000 disability – adjusted life years lost in 2003. In India JE virus activity was detected in 1952 through serological surveys. Cases of JE were clinically diagnosed in 1955 in North Arcot district of Tamil Nadu and the isolation of JE virus from mosquitoes also took place in the same year. Japanese encephalitis has emerged as a major public health problem in India since the early 1970s when a series of outbreaks occurred in various parts of the country. The first major JE epidemic in Uttar Pradesh occurred in Gorakhpur in 1978 with 1002 cases and 297 deaths were reported. Gorakhpur very recently (2005) faced a devastating epidemic outbreak affecting 6097 individuals with 1398 deaths. In intensity and magnitude, this epidemic surpassed all previous reported epidemic outbreaks. The clinical and sub clinical rate has been calculated to be 1:270 (Gajanana et al. 1995). Even if clinical to sub clinical ratio is taken as 1; 100 annually, nearly five million individuals get JE virus infection. The mortality rate is 25% to 40% and 60% to 70% of the survivors have very severe neurological sequelae. JE is a zoonotic disease, affecting many species of animals and birds of which pigs and ardeid birds are known to be important maintenance and amplifying hosts for the virus. Man is a “dead end” host, playing no role in the maintenance cycle. Culex tritaeniorhynchus, the primary vector of JE breeds in paddy fields, irrigation channels, rainwater pools and seepages. The epidemiology of the disease is still not clear and remains highly complicated with several missing links. The seasonal incidence of JE varies in different parts of India. In West Bengal, the disease occurred between May and October, and was shown to be related to the summer monsoon. In Tamil Nadu, 64% of all cases have been reported in the monsoon months of October to December. In Karnataka, the majority of cases in Kolar district occurs during October to December while in Mandya district there is an unique bimodal incidence of JE, 9

corresponding with the two main rice crops in the area. In Kerala, Japanese encephalitis outbreak occurred between January and April coinciding with rice cultivation. In Assam JE epidemic was confined to the peak monsoon months of July and August (96% of the cases in the past). In Uttar Pradesh, Gorakhpur has been experiencing outbreaks of JE since 1978 during the months of August and November. In Arunachal Pradesh maximum cases were recorded between June to October. JE virus has established itself in Maharashtra and cause serious public health problems during the months June to December. An epidemic of encephalitis occurred in the eastern, paddy growing districts of Haryana state between July and November. JE cases occurred in Andhra Pradesh in September-October months coinciding with peak vector density. JE outbreak control measures are undertaken when epidemics do happen are of little consequence as far as decreasing morbidity and mortality. There is, therefore, a requirement of JE prevention being taken up as an ongoing programme, rather than an emergency reaction.

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BIOLOGICAL TREATMENT OF WASTEWATERS: WASTE STABILIZATION PONDS B.B. Hosetti Department of Applied Zoology, Bio-Science Complex, Kuvempu University, Shankaraghatta - 577 451, Shimoga District, Karnataka, INDIA. e-mail: [email protected]

These are important biological treatment systems mostly used as secondary treatment facilities to improve the effluent quality specially in tropical areas where sun light is plenty and land costs are low. These may be used as alternate to conventional treatment plants namely, Biological filters and Activated sludge plants. The treatment occurs by natural, physical, chemical and biological processes in shallow stabilization pond without any external interference. Waste stabilization ponds are low cost waste recycling dynamic ecosystems comprising of bacteria, algae, viruses, fungi, protozoa, rotifer, insects and crustaceans, As these organisms can coexist and compete with each other for survival and the organic content of the waste stabilization ponds produce high quality effluents. The economic value of the stabilization ponds is determined by quality of effluents for irrigation, fish rearing, duck, prawn production and for algal protein extraction. The disadvantage of these systems is requirement of large areas for construction of ponds, Mosquito breeding in the catchment area might be flooded in to these stabilization ponds wherein integrated mosquito management measures can be implemented very effectively.

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SIGNIFICANCE OF LARVIVOROUS FISH IN PUBLIC HEALTH Reddya Naik. B, Umamaheshwara Reddy. P* and Rajesh Kumar. A Dept. of Zoology, P. G. College of Science, Saifabad, O. U. Hyderabad. A. P. -500 004. *Dept. of Zoology, Osmania University, Hyderabad. A. P. -500 007.

Usage of Larvivorous fish has been widely used in public health, since as early as 1903. Though, many time tested mosquito control methods exist but many of them need repetitive efforts to tackle mosquito breeding, whereas larvivorous fish is a self replicating and capable enough to keep a check over the mosquito breeding as well as promotes a good source of food chain in any given habitat. In laboratory conditions with a single female fish eats about 80 to 100 mosquito larvae per day whereas the same fish could feed only 25-30 mosquito larvae per day in urban sewage field conditions despite it stands good in controlling mosquito larvae due to its perpetuating abilities. In these circumstances popularization of the usage of larvivorous fish such as Poecilia reticulata, (Peters) Gambusia affinis (Girard) in a sustained manner is the need of the hour.

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PERSPECTIVES AND PROBLEMS OF INTEGRATED MOSQUITO CONTROL A.K.Hati1 and D.C.Saha2 1. Former Director, Calcutta School of Tropical Medicine, Kolkata 700073. 2. Teacher, Belgharia High School,Kolkata 700056.

In a portion of Salt Lake City, 24 Parganas, West Bengal employing integrated control measures including fenthion, guppy fish, painting red colour on gully pits to repel mosquitoes, a significant reduction of mosquito larva was achieved, in comparison to another portion of the city. Bacillus thuringiensis toxin was successfully employed in mosquito larva control operation in Howrah town and in some areas of Kolkata Corporation. 836 persons suffered from malaria in Kolkata of whom 670(80%) did not use mosquito nets. 342 persons did never suffer from malaria in Kolkata out of whom only 11(3.2%) did not use mosquito nets. With water velocity~ 3 cm/sec, larvae were washed away. The higher the salinity the lesser the existence of larvae. On the other hand alkalinity favoured mosquito breeding in stagnant water collections. The less dissolved oxygen, the less number of larvae in water bodies was found. Neem seed oil, an excellent repellent was successfully tried in the field that prevented all sorts of mosquitoes for at least 6 hours. In laboratory experiments, arthropods like Shaerodema annulatum, Laccotrephes maculatus, fungi like Coelomomyces, Aspergillus, bacterial toxin of Pseudomonas pyocyanea were excellent killer of mosquito larvae. During dengue epidemic in kolkata in 2005, source reduction was attempted which paid a good dividend. More men (20%) than women (8%) used repellents, knew birth places of mosquitoes around houses(20%vs72%), and searched breeding places of mosquitoes(68% vs. 32%). All these were examples of weapons used in integrated vector control. These are to be used judicially, with the active involvement of the whole community, with adequate monitoring, keeping in view emergence of resistant species of mosquitoes, non-compliance, whether using in a piecemeal manner, whether proper plans and programmers are formulated, etc. Genetically modified insect vectors would no longer be able to transmit pathogens. This would be a reality in near future. Yet then such transgenic mosquitoes for example Ades aegypti might not transmit dengue, but could be the potent vector of other deadly viral diseases.

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FUTURISTIC TOOLS FOR PUBLIC HEALTH PROGRAMS: DECISIVE GAINS IN PREVENTION & CONTROL OF VECTOR BORNE DISEASES B Krishnakumari Pheromone Group, Organic Division-I, Indian Institute of Chemical Technology, Hyderabad – 500 007, India.

High population densities and breakdown of sanitation facilities lead to propagation of insects and rodents. Blood feeding insects transmit many serious infectious diseases in tropical countries of Africa, South & Central America and Asia. Of the 10 infectious diseases listed by the World Health Organization (WHO) that disproportionately affect the world’s poor and marginalized populations, insects transmit 7 diseases. Parasitic diseases spread by the bite of insects, effect nearly 350 million in 88 countries – of which 90% live in India, Bangladesh, Brazil, and Nepal & Sudan. One million new cases per annum are reported and, sometimes, what arises as an emergency situation might develop into a full-blown epidemic of malaria, filariasis, dengue, chikungunya, Japanese encephalitis etc transmitted through mosquitoes and kala-azar or leishmeniasis transmitted through sandflies. Current disease control programs in India and the world over are focused on the prophylactic and therapeutic use of anti-malarial, anti-viral and anti-leishmanial drugs. However there can be resistance to these drugs and the longer treatment regime (> 20 days) is associated with side effects. Hence, public health measures to reduce the vector population near human/animal reservoirs are important. This is possible only by preventing infected-insect bites as the most immediate form of protection. Treating vector habitat with insecticides alone would attract mating aggregations of insects to alternative nonpesticide treated sites. Therefore there is still a pressing need to consider and explore alternative and/or complementary strategies for reducing disease transmission by integrating all available control methods while continuously monitoring/controlling vector populations using trapping devices. However, further evidence of the role of human odors on differential attraction of Aedes, Anopheles and Culex species has been established in experimental tents i.e. extent of attraction differ from species to species. In fact, at Sacranebti-Yolo mosquito district, officials are planning to deploy mosquito monitoring trapping devices containing, specially developed “Stinky-Water” lures, prepared in the laboratory from easily available raw materials, which mimic the natural fragrance from larval breeding water bodies. Thus, current research goals have been set to develop a scent, which is better than humans at attracting mosquitoes that might enable the creation of lures that draw the insects away from people into killing traps.

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INTEGRATED APPROACHES TO CONTROL MOSQUITOES AND MOSQUITO BORNE DISEASES Rajni Kant Indian Council of Medical Research (ICMR), Ansari Nagar, New Delhi-110029

Mosquitoes are known to exist on this planet since millennia. There are more than 3000 species of mosquitoes and they cause dreaded diseases like Malaria, Filariasis, Dengue, Japanese encephalitis, Yellow fever and Chikungunya. Control of mosquitoes has always been a daunting task and the advent of DDT in mid 1950s brighten the hope but the euphoria of success short lived and mosquitoes started developing resistance against most of them. In recent few years, the emphasis is now being given on Integrated control of mosquitoes with the inclusion of source reduction, minor engineering methods, Health Education, Community Participation and biological control methods and this has proved successful in certain situations. With the availability of Genomic information and application of new molecular biotechnological tools along with the use of Geographical Information System (GIS), Remote Sensing etc, it is expected that mosquitoes can be controlled in better ways than ever before.

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MOSQUITO MENACE: PRESENT SCENARIO AND ITS MANAGEMENT Sajal Bhattacharya Reader, Department of Zoology and PG Dept. of Environmental Science Asutosh College (University of Calcutta) 92, S.P. Mukherjee Road , Kolkata 700026 , INDIA

Among all the insect vectors of human diseases, mosquito stands out as, by far the most medically important fauna. Apart from being a nuisance, mosquitoes are responsible for the death and incalculable misery of millions of people every year, and are therefore, the numero uno public health enemy. There are considerable evidences for the resurgence and progressive increase of some mosquito borne diseases (MBD). For example, Dengue and Chikungunya have flared up in many countries including India that formerly had them under control. Sudden outbreak of West Nile virus has been reported from USA and some parts of Europe in the recent years. In addition to the above mentioned diseases, Malaria, Lymphatic filariasis, Japanese encephalitis are also endemic in India. Although, Yellow fever (YF) has never been reported in India, yet the region is believed to be a “ Yellow fever receptive area.” Aedes albopictus , the potential vector of several arboviruses has spread from South-east Asia to the USA , Europe and Africa. This species can be referred to as the global vector. There are up to 500 million and 100 million clinical cases of Malaria and Dengue respectively per annum worldwide, encompassing over 100 countries. Malaria causes 3000 deaths per day. The vast majority of cases and casualties occur in Africa. Recent estimates indicate that more than 2 billion people around the globe are at risk of Malaria. The cost of MBD is not restricted to the loss of human life only. Its impact on labour productivity and the resultant loss of man-days imposes heavy burden on society, hindering social and economic development of a country. For instance, Malaria costs the African nations more than US $ 12 billion annually. Lack of effective vaccines ( excepting YF ), emergence of drug resistance, rising cost of drugs and poor delivery systems mean that the vector control remains the key control measure for the MBD/s. Sustained vector and epidemiological surveillance would help to forecast the future outbreak, if any. Early preparedness will be highly useful in combating MBD/s more effectively and efficiently. The objective of the mosquito vector control programmes is to reduce the effect of the disease on the population to a level that is environmentally sustainable, economically attainable and politically acceptable. Amongst the integrated mosquito vector management programme, environmental management has taken a very important role. An environment management plan includes planning and carrying out of activities for the modification and manipulation of environmental factors to reduce the spread of the disease, with a view to preventing or minimizing vector propagation and reducing human-vector-pathogen contact.

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FACTORS ASSOCIATED WITH MALARIA DECLINE IN AN ENDEMIC VILLAGE IN NORTHERN SRI LANKA S. Kannathasan§, KA Srikrishnaraj† and SN Surendran‡* §

Department of Pathology, Faculty of Medicine, University of Jaffna, Jaffna † Faculty of Applied Sciences, Vavuniya Campus, Vavuniya ‡ Department of Zoology, Faculty of Science, University of Jaffna, Jaffna, Sri Lanka

Malaria is of public health importance in war-torn Kilinochchi district in northern Sri Lanka. The disease burden has been attributed to the prolonged civil disturbances in the northeast of Sri Lanka. However, a drastic decline in malaria cases has been reported from this district since 2003. Ariviyal Nagar, a newly established resettlement village for internally displaced people recorded 70% of the case load reported from Kilinochchi District in 2004. A study coupled with active case detection (ACD) and mosquito survey, and a structured questionnaire interview was carried out in March 2005 and 2006 to explore factors responsible for the reduction in malaria cases in the village. The results showed that organized vector control measures, early diagnosis, prompt and complete treatment, and public awareness programmes carried out by health authorities and personal protection measures employed by the residents collectively contributed for the drastic decline in malaria cases.

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PREVALENCE AND CLINICAL FINDINGS OF CHIKUNGUNYA VIRUS DISEASE IN RURAL AREAS OF ADILABAD DISTRICT, A. P., INDIA M. Estari and M. Krishna Reddy Reproductive Physiology Unit, Department of Zoology, Kakatiya University, Warangal – 506 009, Andhra Pradesh, India

This is the first report of Chikungunya (CHIK) viral epidemic in rural areas of Adilabad district, Andhra Pradesh. Objective of this study was to confirm that clinical symptoms can occur in epidemics to identify the association of any pathogen, to estimate the magnitude of CHIK disease in the rural population, to study its clinical characteristics, and pathology to understand the effect of symptomatic treatment. A randomized study was carried out 132 CHIK fever patients. It was performed in clinical laboratory of Adilabad district, Andhra Pradesh State from 1 August 2005 to 28 July 2006. The CHIK fever cases were analyzed for age, sex, symptoms and signs. Both sexes and all age groups were affected by CHIK fever. Incidence was high (56.06%) in females than male (43.94%). In the age group of 51-60 years highest (29.54%) seroprevalence of CHIK fever is observed. Seroprevalence was highest among the rainy season. As a result of epidemic there was no mortality. Clinical and pathological tests were conducted among CHIK patients. Diagnosis symptoms and signs reported in CHIK fever patients included vomiting in 51-75%, severe headache in 26-50%, Maculopopular rash in 26-50%, arthralgia in 76-100%, leukopenia in 76-100% and thrombocytpenia in 1-25%. Arthralgia, maculopapular rash, leukopenia were most common clinical manifestations found. Leukopenia is usually seen and thrombocytopenia is observed in 26-50% of CHIK fever patients. 76-100% Leukopenia and arthralgia found in old age groups of CHIK fever patients.

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“MISSION OF BATS IN MOSQUITO ERADICATION IN THE TROPICAL PLAINS OF INDIA” Juliet Vanitharani Bat Research Laboratory, Department of Advs. Zoology and Biotechnology, Sarah Tucker College, Tirunelveli – 627007, Tamilnadu, India. E-mail: juliet @ sancharnet .in / [email protected]

Among mammals the nocturnal Chiropterans (Bats) are undoubtedly the most gregarious and successful group of animals, beneficial to the ecosystem and mankind. Bats are just one of several groups of animals that naturally prey on mosquitoes. They are both opportunistic and selective in their feeding several factors are involved as to which specific insects are consumed in the greatest quantity. Researches have proved some species of these primary predators consume large number of mosquitoes. Individuals of these species can capture 500 to 1000 mosquitoes in a single hour or two and large colonies can consume enormous quantities. Species representative of the family Vespertilionidae, Emballonuridae, Hipposideridae and Rhinopomatidae of the tropical plain prefers in general soft bodied insects such as moths, flies, midges, mosquitoes and mayflies. Bats fly all night long capturing and swallowing mosquitoes until dawn. This role is critically important in the overall scheme of our ecosystems. People should protect an even encourage bat population. The survey records threaten the decline in bat population. The field proof fecal analysis data is the only weapon to encourage bat conservation. Providing additional bat roost is just one aspect of bat conservation. Built of bat houses at back yard may provide roost for some of these species. Saving bats are just one aspect of enhancing natural control of mosquitoes.

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BIOLOGICAL CONTROL OF MOSQUITO CULEX QUINQUEFASCIATUS BY THE FISH POECILIA RETICULATA IN THE SURFACE DRAINS OF CALCUTTA D. C. Saha* and A. K. Hati *Teacher, Belgharia High School,Kolkata 700056. Former Director, Calcutta School of Tropical Medicine, Kolkata 700073.

The potential to achieve “ Biological Control of mosquito Culex quinquefasciatus by the fish poecilia reticulata in the surface drains of Calcutta” is now more feasible than ever before, as the efficacy of Poecilia reticulata, a newly introduced predator proved successful and hence the suitability of Poecilia reticulata as a classical Biological control agent for mosquito larvae is a reality. The high feeding capacity of Poecilia reticulata on the mosquito larvae, low cost for its application as well as high pollution resistance were remarkable assessment in my understanding for the application of this agent in the drains of the study area (Krishnapur and Narikeldanga). The plan of work was to depict the larval densities of the drains of Kishnapur and drains of Narikeldanga. Survey of larvae was carried out in the drains of Krishnapur was done and then were released Poecilia reticulata in those drains for the bioassay of larval fauna. Comparative degree of control was attained. Significant reduction of larval density occurred in the drains as well as in the laboratory. Natural habitat of Poecilia reticulata and mosquito larvae in drains of Narikeldanga pointed out that the larval densities were significantly lower in presence of Poecilia reticulata. Seasonwise variation in the larval density related to survival of Poecilia reticulata was remarkable. The distribution of fish fauna in drains of Narikeldanga did appear to substantiate that Poecilia reticulata survived and contributed to the total biological control efforts. Another observation was noticed in drains of Krishnapur where the larval density was high. The application of chemical methods using larvicide (diesel oil) caused a drop in the larval density of Culex quinquefasciatus. But some level of resistance development in the population on Culex quinquefasciatus. Physical and chemical factors of the water of different breeding places were estimated by standard methods and correlation of these factors with the larval density of Culex quinquefasciatus was sought. For the survival of Poecilia reticulata the suitable temperature was between 20.5oc C and 30.5oo C, suitable pH from 6.8 to 7.2, dissolved oxygen content varied from 0 to 4.42 and salinity from 4.2 to 178.9 mg/l. 20

ECO-FRIENDLY APPROCHES FOR MOSQUITO MANAGEMENT G. Venkat Raman P.G. Department of Zoology, Vivek Vardhini College, Jambagh,Hyderabad-500 095.

Aedes aegypti, popularly known as Tiger mosquito, is vector for deadly diseases like Dengue, Chikungunya and Yellow Fewer in the tropical countries. Since its feeding habit is different and coinciding with working hours during daytime, domestic control measures at nighttime are not practicable. The mosquito can travel long distances, so controlling at one area may not useful. The data collected from different municipalities and local bodies suggest that practicing single method like chemical fogging has not been a successful method. Further, it caused public inconvenience and respiratory disorders. The only alternative method is Integrated Mosquito Management (IMM), utilizing all available methods at community level along with domestic control. In Integrated method, breeding site reduction in home, office and workplaces and controlling the wriggler and tumbler stages in stagnated water bodies and agricultural irrigation sources is important method. Chemical control like fogging and using repellents, fitting mechanical barriers like mesh to windows and doors and arranging chemically treated bed nets are further steps in this method. Research results revealed that chemical treatment has contaminated the water bodies and killed the fauna. Alternative eco-friendly measures are; using microbial larvicide like Bt israeliensis , IGR- Methoprene and introduction of larvicidal fishes in the water bodies or breeding sites. Laboratory studies have revealed that, botanical pesticides like Neem and Annona and Karanj extracts are the other eco-friendly chemicals which could be used for the control of larval stages effectively. Using citronella oil as adult repellent, wearing light colored long sleeve clothes are other safe measures.

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EMERGING TRENDS IN MOSQUITO MANAGEMENT Anil Kumar Makkapati Senior Manager – Business Development (Vector Control) and Technical Services Bayer Environmental Science, Bayer CropScience Limited Bayer House, Central Avenue, Hiranandani Gardens, Powai, Mumbai – 400 076 E mail:[email protected]

Historically mosquitoes are one of the most important insects encountered by man because they are vectors of human diseases such as malaria (protozoa), filariasis (nematodes), chikungunya, dengue and the Japanese Encephalitis (arbo-viruses). It has been estimated that half of all human deaths prior to 1950 (the dawn of miracle insecticides) resulted from mosquito-transmitted diseases. The dependence on the pesticides is still the major tool to combat mosquito vector menace. Among the methods used to manage mosquitoes, larviciding, Indoor Residual Spray, fogging and use of insecticide treated bed nets are being practiced by various government and semi government organisations. In India, mosquito borne diseases annually affects several millions of people. Conventional pesticides such as DDT, malathion, temephos, deltamethrin etc., are being used over years. There are several published/ unpublished reports of insecticide resistance/tolerance to these conventional products. There is a need to review our current insecticide portfolio and introduce new products/ technologies in to our mosquito management strategies. Among the emerging trends, rotation of insecticides with different modes of action as a insecticide resistance management, tendency in Insecticide Treated Nets to long lasting wash resistance bed nets, in fogging the use of water based products, increased use of larvicides with target specific mode of action (eg., IGRs), development of longer lasting Indoor Residual Spray formulations, strategies involving Integrated Mosquito Management (IVM) principles, search for new safer formulations are being focused both by Industry and Govt Organisations. Bayer Environmental Science is one of the pioneers in the field of mosquito vector management by introduction of new products and strategies. During the presentation, products and strategies, which can be offered by Bayer, would be discussed.

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“MOSQUITO MENACE? FROG BREEDING!” M. Srinivas Badruka College of Commerce, Kachiguda, Hyderabad-27. Tel.No.24732832; Res.24651330, E-mail: [email protected]

In wake of the Mosquito Menace, which is causing very strange and unheard diseases like Dengue, Chikungunya etc., there is an urgent need to address this menace through natural process only. And the answer lies in breeding varieties of Frogs all over the country. This menace has not surfaced suddenly it is the result of systematic extermination of all the species of Frogs from ponds, lakes and rivers from all over the country. Since 1956 onwards Frogs are being killed in very large numbers and are being exported to foreign countries. Thus we are facing ecological imbalance. Under the sub-theme ‘Mosquito Ecology and Biodiversity’ this paper entitled “Mosquito Menace? Frog Breeding!” is being attempted to find a reasonable cost effective and natural solution to the problem.

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DENSITY OF IMMATURE MOSQUITO FAUNA IN HYDERABAD MUNICIPAL SEWAGE WATER Reddya Naik.B, Umamaheshwara Reddy. P* and Rajesh Kumar. A *Dept. of Zoology, P.G.College of Science, O.U. Saifabad. Hyderabad A. P- India Dept. of Zoology, Osmania University, Hyderabad, A. P- India.

Mosquitoes designed to breed quickly and in very large numbers in different types of water bodies. Municipal sewage water is one among such habitat that suffices to complete the life cycle of mosquito. The network of sewage disposal is unbearable to the rising populations in urban areas; constant choking and debris lead to formation of tiny eddies/ puddles in sewage canals, where the potential mosquito breeding was noticed. Mosquitoes concerned with public health are: Anopheles, Aedes and Culex, all of these were breeding or storm flooding in sewage water with varied densities along with their specified breeding habitats. Present investigation was aimed to assess mosquito larval density in municipal sewage water. Culex quniquefasciatus species density was dominant (1275 MLPD) than others, and malarial vector Anopheles Cellei subpictus was recorded as a satellite species in washer men wells along the Musi riverbank.

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PUBLIC HEALTH IN GLOBALIZATION ERA – A REVIEW Reddya Naik Bannoth and Umamaheshwara Reddy Pulkurthi.* Dept. of Zoology, P.G. College of Science, Saifabad (OU), Hyderabad, A. P - 500 004, *Dept. of Zoology, Osmania University, Hyderabad, A. P- 500 007.

Public health is an art and science of preventing diseases, promoting health, and extending life through the organized efforts of society. In the process of globalization there is a systematic crisis in the field of public health. In fact globalization of diseases is begun with European colonization way back in 15th century. In the tropics and subtropics, population growth, unplanned urbanization and its commonly associated deficiencies of water supply and solid waste management, together with increasing international travel and other factors are responsible for the emergence and resurgence of vector-borne diseases such as Chikungunya, Malaria, Japanese encephalitis, Dengue, St. Louis encephalitis, Yellow fever and West Nile virus. There are a number of different dimensions to the movement of people and materials around the world that affect the distribution and incidence of vector-borne diseases. People can either act as carriers of pathogens into new environments or accidentally translocate vectors in transport vehicles. People can also become victims of vector-borne diseases when they travel to new countries where they are exposed to diseases for the first time. Such people are usually naive to the disease, and thus morbidity and mortality rates are relatively high. Future health prospects depend increasingly on globalization processes and on the impact of global environmental change. The aim is to assess the risks of potential changes in the status of vector-borne diseases in a changing world and to consider approaches to effective adaptation to those changes.

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APPLICATION OF REMOTE SENSING AND GIS IN MALARIA CONTROL T.K. Pavan Dayaker and A. Rajesh Kumar* Lecturer in Environmental Sciences, Loyola Academy of PG and Degree College, Hyd. * Vector Biology and Control Lab, Department of Zoology, P.G.College of Science, Saifabad, Osmania University, Hyderabad 500004

Malaria as said by the Government that it has been completely eradicated from India. Can we have complete faith in these words, no not at all? Even today we see many such cases were the people are dying with malaria. Then how come these diverse situations between the people and government. All these misunderstandings are because of improper management and maintenance of the files. As in may cases we do not have a proper record of the cases that come to the hospitals, not only malaria but not for any case. Malaria spreads through varies conditions closely related to the habits and lifestyle of different communities, the behaviour of the mosquitoes which transmit the disease; as well as climatic and other environmental attributes. Many scientists working in this field, following the elucidation of the malaria cycle in man and mosquitoes, appreciated that it was a focal disease and that the topography of the land was an important consideration in understanding the local epidemiological situation. For any land related survey the latest technology is utilization of the remote sensing and geographical information system. These tools helps the scientist is fast and accurate decision making. In this technique the data can be stored in spatial and attribute database form. The attribute data can be shown in both the form spatial and non spatial. Any data will make more sense when we view it rather than reading the reports. GIS mapping software provide powerful tools for management and analysis of malaria control. The management skills include: preparation of base map or the operational maps, program for monitoring and evaluation, creation of the database and linking the database to the spatial map (topography, land use, roads, rivers, surface water) and the final output according to the user. These could include data on population distribution (towns, villages and hamlets); location of health centers and other facilities (hospitals, health posts, dispensaries, schools, government offices); meteorological indices (rainfall, temperature, humidity); epidemiological data (morbidity, mortality, parasitological indices, mosquito distribution records); and any other data which can be referenced geographically. This computer based technology has been available for a number of years but it is only recently that it has been widely appreciated. The use of Remote sensing and GIS as a malaria research tool is a worthy objective, at national or international levels. This research should lead to further insights into malaria epidemiology and the complexity of its transmission potential in endemic areas and be used for the protecting human life. 26

PLANT PRODUCTS IN VECTOR CONTROL M. Marthanda Murty Scientist, Organic Chemistry Division Indian Institute of Chemical Technology (CSIR), Hyderabad 500007.

Mosquitoes are responsible for more diseases than any other group of arthropods, being the major Vector for the transmission of life threatening and debiliating parasitic and viral diseases including malaria, filariasis, yellow fever, dengue and different forms of encephalitis. The incidence of mosquitoes borne diseases depends on controlling mosquito population by means of chemical insectcidies, physical methods or by drugs to prevent infection. Repeated usage of chemical insectides has fostered environmental and health concerns and also resistance and undesirable effects on non target organisms. Natural products are considered potentially important alternative tools for the control of insect pests including mosquitoes. Plant derived natural products are important source of biologically active compounds for controlling insect pests like mosquitoes. Methodology for the extraction, isolation and identification of these compounds from plants with suitable examples will be the objective of the paper.

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RESPONSE OF PEOPLE IN HYDERABAD TO MOSQUITO PROBLEM & ITS MANAGEMENT I. Suryakala*; B. R. Naik; B. Joyothi* and G. Sunitha Devi *Department of Zoology, Nizam College, Basheerbagh, Nampally, Hyderabad – 500001 Dept. of Zoology, P.G.College of Science, O.U. Saifabad. Hyderabad A. P- India

Mosquitoes often make life miserable for human, poultry and live stock. They are vectors of important human and animal diseases and may need to be controlled either through individual or community effort. In cities, resident co-operation and city managed abatement programmes are essential in controlling and managing mosquitoes over a large area. When different areas of Hyderabad district were surveyed in 39 areas, in 975 houses for people’s response to mosquito problem by government, communities, associations and general. The observations revealed that the government activities were seen about 36.3% and rest of the 2/3rd people felt that the government activities has tobe intensified in tackling the mosquito menace.

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ADVERSE EFFECTS OF MOSQUITO REPELLENTS -A SURVEY B. Jyouthi, B. Reddya Naik* and I. Suryakala Department of Zoology, Nizam College, Hyderabad *Dept. of Zoology, post Graduate College of Science, Osmania University, Saifabad, Hyderabad-4.

Mosquitoes are the most abundant group of organisms on earth that act as vectors of many diseases. Hyderabad is exposed to mosquito menace causing many health hazards. Chikun gunya and Dengue are recent manifestations of the diseases caused when the female mosquito, which acts as a carrier, bites to obtain blood. People are using different types of repellents to control mosquitoes. The present study is the survey of adverse effects of repellents in different areas of Hyderabad. Out of 975 people questioned, 5.5% reported of having developed respiratory disorders, 7.2% complained of uneasiness, 14.36% complained of common cold, 15% reported of a headache and 63.3% said that they did not notice any adverse effect. The results clearly hint on the adverse effects of repellents on human health.

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AWARENESS OF MOSQUITO CONTROL PRACTICES IN COMMON MAN G. Sunitha Devi and B. R. Naik Dept. of Zoology, post Graduate College of Science, Osmania University, Saifabad, Hyderabad-4

Source reduction the most important step is reducing the numbers of mosquitoes to eliminate their breeding places. Mosquito repellents generally contain are of the following active ingredients: DEET (Diethyl to toluaminde), catnip oil extract, nepetalavetone, citronella, or eucalyptus oil extract. Often the best ‘repellent’ is a fan or gentle breeze as mosquitoes do not like moving air. DEET is a highly effective repellent against mosquitoes, especially when worm in conjunction with light coloured clothing and a hat to cover the head. The present study, covered with defferent socio-economic background of the people in practicing some or the other methods to keep of the mosquitoes. Many people were not aware about the exact breeding phenominon of mosquitoes and mainly depends on the products available in the market to tackle the adult mosquitoes. In Hyderabad district with the sample size of 975, in 39 areas revealed that 43.4% people were regularly practicing, about 18.9% were practicing now & then, 5.4% people practicing seasonally, people practicing occasionally, 7.3% and 3.6% people were not practicing any method of mosquito control .

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MOSQUITOES CONTROL MEASURES IN PRACTICE *B. Neeraja; B.R. Naik; G.Sunitha Devi and I. Suryakala *Dept. of Zoology, University college for women, Koti, Hyderabad. Dept. of Zoology, post Graduate College of Science, Osmania University, Saifabad, Hyd -4

In general there are two kinds of mosquito control: Large, Organized programs – to reduce mosquito populations over a wide area, and action of individuals can take to control mosquitoes with respect to themselves and their own property. Other popular methods of household mosquito control include use of small electrical mats, mosquito repellent vapour and mosquito coil, all containing a form of the chemical allethrin. Mosquito repellent candles containing citronella oil to keep mosquitoes at bay. Present study was the survey on “ Type of control measures being practiced by common people”, in 39 areas and considered 975 houses. The present investigation revealed that 76.3% people of 744 houses, using repellents and 23.7% i.e. 231 houses showed no response. The second topic of survey was “ Type of control measures – No specific”, in 39 areas & considered 975 houses. This showed that people using any one or more methods of control measures like mosquito proofing, repellents, mosquito nets and fumigation, but not specific method. 93.4% of people using any one or more methods of control measures but not specific, and 6.6% people using only one method selectively.

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INCIDENSE OF CHIKUNGUNYA VIRAL FEVERS IN NALGONDA DISTRICT OF ANDHRAPRADESH G. Kranthiprakash and K. V. Ramana Kamaneni Institute of Medical Sciences, Narketpally.

Chikungunya fever in Swahili means “that which contorts or bends up” refers to the contorted (Stooped) posture of patients who are afflicted with severe joint pains (arthritic) which is the most common feature of the disease. It is caused by “Chikun gunya virus” belong to Genus: Alfa virus (Group-A) of Family: Togaviridae. Chikungunya occurs mainly in Africa and Southeast Asia with a number of out breaks in islands throughout the Indian ocean. The viral illness spreads by the bite of infected female Aedes aegypti mosquito, which bites during date and rest in dark corners or under furniture. Chikungunya established itself as an endemic infection and was continously transmitted among urban population, Major epidemic occured in Srilanka and Madreas in 1964 and 3,00,000 cases were reported in a population a about 20, 00, 000, during the last 1950s and 1960s. Chikungunya viral fever started occurring in Rayalaseema districts from December 2005, the disease slowly spread to other districts in the State. In Nalgonda dist. Chikungunya fever reported from 15-12-05 covering 2, 27, 581 population in 25 Mandals of 84 Villages. 2496 cases were reported 23 were found positive. The disease is characterized by sudden fever Chills, Headache, Nausia, Vonitings and severe joint – pains. Incubation period is 2-4 days with an abrupt onset. After 1-4 days the fever subsides, joint pains occurred up to 4 weeks evidenced by redness, swelling and tenderness of inflamed joints. Mortality in less then 1%. There in no specific treatment for Chikungunya supportive therapy that helps to ease symptoms, administration of non-steriodal anti-inflammatory drugs and giving rest may be beneficial. Infected persons may be protected from mosquito bites, and control of mosquitoes through chemical, biological and environment methods. Patient care, management are the key issue in prevention and control of Chikungunya out break.

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DENGUE IN NCT DELHI R. S. Sharma, Joint Director National Vector Borne Disease Control Programme, 22, Sham Nath Marg, Delhi 110 054

Dengue fever / dengue haemorrhagic fever continues to be a major infectious disease of public health importance in countries of the western Pacific and South-east Asia regions. These regions are experiencing a geographical spread, both in terms of distribution of the virus and mosquito vector, with an increase in the frequency of epidemics. Since 1963, outbreak of dengue/ DHF has been recorded in almost all parts of India except the northeastern region. In all the outbreaks the main mosquito found to be involved in transmission was Aedes aegypti. However, during the outbreak in Kerala state during 2004 the vector involved in the transmission was Aedes albopictus. The first outbreak of dengue fever in India with haemorrhagic manifestation was reported in Calcutta city. Increasing trend of Dengue outbreaks accompanied by Dengue Haemorrhagic fever is posing a problem of utmost importance to public health in India. Dengue fever outbreaks have been reported from various parts of the country during the past 30-40 years. A severe outbreak of Dengue haemorrhagic fever swept National Capital Territory, Delhi in 1996 wherein 10,252 cases and 423 deaths due to DHF were recorded in various parts of Delhi. Delhi has been endemic for Dengue since past several years. The first DHF outbreak was reported in 1988 with 33% mortality among children admitted in hospitals. The principal vector of Dengue fever Aedes aegypti is prevalent in all Metropolis, cities and towns of India. The gangetic plain of North India is also infested with Aedes aegypti. Although Aedes aegypti has been known to be widely distributed in several countries of South east Asia and its importance as potential dengue fever vector has been recognized since long, the information on its prevalence and shifting trend of breeding places is still fragmentary. Vector surveillance is an important tool to generate entomological data for suggesting appropriate control strategy and developing an early warning system. The studies on the dengue incidence and Aedes aegypti prevalence were conducted in Delhi during 2006. Aedes population was reported in priority areas like hospitals and schools in Delhi.

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STUDIES ON THE REVERSION OF INSECTICIDE RESISTANCE IN AN. CULICIFACIES IN DISTRICT SURAT, GUJARAT K. Raghavendra and A.P. Dash National Institute of Malaria Research, 22 Sham Nath Marg, Delhi [email protected]

First reports of resistance in An. culicifacies to different insecticides used in public health sprays were from the state of Gujarat. Reports of resistance to DDT were reported in 1958, to dieldrin in 1959, BHC in 1962, malathion in 1973 and to deltamethrin in 2002. Successive replacements with more effective insecticides belonging to different groups of insecticides to mange the disease vectors has led to development of multiple resistant vector species. Subsequent to development of resistance to DDT and BHC, malathion was introduced in 1969 and in early 1990s pyrethroids were introduced for Indoor residual spray (IRS) to control this vector. However, IRS was discontinued since 2002 due to low annual parasite index (< 2) in the area. Our earlier studies in the years 1986, 1987, 1992 and in 2002 have shown this species to be multi resistant to different insecticides. But, in our recent studies in this district in the years 2005 and 2006, this species was found to be moderately resistant to DDT and malathion and susceptible to other organophosphate and pyrethroid insecticides. Discontinuation of IRS might have substantially reduced the insecticide selection pressure on this species thereby resulting in the reversion in the resistance. An. culicifacies in this region is further found to be a complex of three morphologically indistinguishable sibling species, species B, C and E and have shown differential susceptibility to insecticides. Results of the studies on susceptibility, mechanisms of resistance and differential susceptibility to insecticides will be presented in the work shop. The above results and the factors responsible for reversion of resistance in the insect vectors will be discussed in detail.

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GENETICALLY MODIFIED MOSQUITOES FOR VECTOR CONTROL – A PERSPECTIVE K. Raghavendra, P. Sharma and A.P. Dash National Institute of Malaria Research, 22 Shamnath Marg, Delhi 110 054 [email protected]

Chemical insecticide based intervention forms the major component of vector borne disease control programmes world over. Development of insecticide resistance in vectors was one of the reasons for the failure to control the disease. Genetic modifications using the recombinant DNA methods can be used routinely to transform the insect vectors for use in vector control programme in future. These can be used to eradicate the wild populations of vectors of the disease and restrict the transmission of the disease. Genetic manipulation by recombinant DNA methods require methods for efficient and stable insertions of foreign genes into the genome of the insects and the availability of useful genes, as well as appropriate promoter and regulatory elements to obtain effective expression of the inserted genes in space and time. This review summarizes the progress made towards development of transposable element vectors, identification of suitable transfer methods to deliver genes for the transformation. The presently available methods for genetic manipulation of mosquitoes, ongoing projects in different insect vectors, issues related to risk assessment in use of such modified vectors for their control by permanent release into the wild will be discussed.

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ISOLATION OF FOUR BACILLUS STRAINS FROM SOIL AND THEIR EFFICACY AGAINST ANOPHELES CULICIFACIES S. S. Mohanty, K. Raghavendra, V. Verma, A. P. Dash National Institute Of Malaria Research, Indian Council Of Medical Research, 22-sham Nath Marg, Delhi-110054, Email: [email protected]

Bacillus-based bio-toxins are gaining importance in the control of insecticide-resistant populations of insect pests and vectors of human diseases. Bacillus thuringiensis is a grampositive bacterium present in soil, water, and on plant surfaces. It produces characteristic protein inclusions during sporulation, which, when ingested, are toxic to a variety of insects and are in use in vector control programme. Studies were carried to isolate bacterial strains from soil to find new virulent strains. Soil samples were collected from locations in the vicinity of mosquito breeding habitats of Delhi and Himachal Pradesh in asceptical conditions. Five strains of Bacillus were isolated from the Delhi soils and three from the Himachal Pradesh following standard methods. Out of the five strains of Delhi, two were found to be entomopathogenic and coded as MB-1 and HB-1. One strain of Himachal Pradesh was found to be effective against mosquitoes and coded as HP-1. The efficacy of the three strains against Anopheles culicifacies species A were tested after growing them for 48 hours in LB+NYSM media. Among the three strains, MB-1 was found to be more effective than the other two strains. MB-1 is 2-fold more effective than the HB-1 based on the calculated median lethal dose. These coded strains are sent to MTCC (IMTECH), Chandigarh for identification. Detailed results will be discussed in the workshop.

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INTEGRATED GEOSPATIAL SOLUTION FOR MOSQUITO CONTROL P M Bala and A Perumal National Remote Sensing Agency, Dept of Space, Govt. of India [email protected]

Environmental degradation, socio-economic decline, and extreme weather patterns are contributing to changing pattern of morbidity and mortality and posing serious challenge to public health. The problems of health are increasing in both spatial and temporal dimension to many newer places, especially in the rural areas due to increased risk of disease transmission fuelled by developmental activities, demographic changes and introduction of newer products. Malaria is still a major public health problem. In India, nearly 2-3 million cases occur every year with about 1000 deaths. Control of malaria requires case detection and treatment of affected individuals and for curtailment of malaria transmission, control of mosquito vectors is paramount. Vector control requires knowledge of the ecology of breeding and resting habitats and behaviour of various species of mosquitoes. The life of mosquitoes is influenced by variations in climatic conditions, and hence there is diversity in the distribution and habitats of different vector species. Periodical surveys are essential for arriving at any conclusion for developing vector control strategy. Routine entomological surveys over vast geographic areas are impractical, time consuming and expensive and therefore are confined to limited areas. Modern tools like remote sensing and Geographical Information Systems (GIS) have now come in handy to address the issues on the disease surveillance, control, monitoring and evaluation. Today, with advanced knowledge on the principles underlying the disease transmission dynamics, prediction of occurrence of diseases is possible based on environmental factors and satellite-based remote sensing data together with GIS technology for data processing and management. Essential tasks for all mosquito control operations are the mapping of potential mosquito breeding sites, the delineation of actual breeding sites for treatments, and the guarantee of high application accuracy. GIS and GPS are indispensable tools for these tasks. Computerised spatial databases including vector-based maps like soil maps, landuse maps, ortophotos, high-resolution satellite imagery, and digital terrain models (DTM) and GIS software provide powerful tools for management and analysis of malaria control programs.

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For mapping of potential mosquito breeding sites, DTM’s generated for satellite data and air-borne laserscanning can be employed to specify potentially flooded areas. During floods, actual water lines can calibrated with height regions based on the DTM by GPS measurements in the field. This allows to extrapolate inaccessible areas with sufficient precision. GIS can also be used to delineate differences in vegetation, topography, field size and water sources to help mosquito control personnel and range managers better utilize Integrated Pest Management (IPM) and the use of reduced risk control techniques to more effectively control mosquito populations. The use of this technology can be tailored to suit a wide range of applications. These include: practical operational maps to assist with resource allocation; analytical tools to facilitate program monitoring and evaluation; and sophisticated research projects to investigate various spatial aspects of malaria epidemiology. A GIS based information management system ensures that if a localised spurt of the disease occurs, it can be associated rapidly with a likely cause, a specific vector, and a probable human source, so that appropriate preventive action can be taken to arrest any rising trend. The foregoing account indicates that RS and GIS technology has provided a tool for mapping the breeding habitats of anopheline mosquitoes, prediction of densities of vector species and even development of risk maps of malaria. It may not be helpful for delineating the smaller habitats particularly container breeding, overhead tanks, stored water, etc. which are usually prevalent in urban areas. The purpose of Remote Sesning is not to detect the mosquitoes, but the indirect parameters of their ecology and behaviour which help in thriving of vector species. Remote sensing and GIS is likely to become a rapid epidemiological tool for surveillance of vector-borne diseases and malaria in particular. Detection of water quality parameters will further help in the detection of the species specific habitats of malaria vectors. The meteorological satellites derived environmental parameters particularly NDVI are likely to serve as indicator for early warning system for malaria. Coupled with GIS, statistical analysis, sound knowledge of ecology of mosquito vector populations, improved remote sensing and GIS technologies will play a key role in the macrostratification of vast malarious areas for prioritizing the control measures in a cost effective way and would provide the requisite knowledge to promote global effort for eradication and control of malaria.

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BIOLOGICAL CONTROL OF DISEASE VECTORS Mr.T.Ratna Joseph, MSc, DEM, Medical Entomologist Health, Medical & Family Welfare Department Government of Andhra Pradesh, Hyderabad -500 020.

Biological control is not a new idea, its importance was recognized even from the early days of human history. There is now a great deal of interest in the development of biological control agents for variety of reasons. World Health Organization, 1982 defined it as “the control of pests, including the vectors of human diseases by direct or indirect use of natural enemies with or without their metabolites”. Natural control system operates through a large number of ‘abiotic’ and ‘biotic’ factors relative to other organisms in ecosystem is ‘balance of nature’. Combined use of biocontrol agents such as predators, parasites and other pathogens can bring about rapid reduction of target populations sustaining the abatement of rebounding vectors. Use of biological control agents will promote conservation of natural enemies which is essential for implementing long-term, cost-effective strategies and minimizing treatment intervals. In the case of invertebrate predators there is a characteristic time-lag between inoculation and build up of sufficient numbers to achieve control. Microbial pesticides however, provide rapid control of initial populations without destroying natural predator species and other non-target organisms. Integration of biological control in to the frame work of well planned Integrated Vector Management (IVM) can have significant impact on vector populations. Introduction of bio-control agent will affect pest equilibrium position, rather than regulatory mechanism. Some of the natural enemies used in biological control programme include larvivorous, phytophagus and omnivorous Fish, Insects, Nematodes, Protozoans, Bacteria, Fungi and Virus,. Advantages of biological control include minimum environmental pollution and health hazards, safe to non-target organisms, ease of production at local level, reduction in operational cost and less likelihood of resistance development. Desirable attributes of biological control agent are.. · · · · ·

Possible to collect or produce in sufficient numbers, Able to persist in pest environment, Able to limit pest numbers below economic injury levels, Should not destroy other bio-control agents, unless it is able to take their place. Must provide predictable level of control.

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LARVICIDAL ACTIVITY OF EXTRACTS DERIVED FROM CHLOROXYLON SWIETEINA Reddya Naik Bannoth, Umamaheshwara Reddy Pulakurthi* and A. Rajesh Kumar Dept. of Zoology, Vector Biology & Control Lab, P. G. College of Science, Saifabad (OU), Hyderabad. A. P. -500 004. India. *Dept. of Zoology, Osmania University, Hyderabad. A. P. -500 007. India.

In most of the Indian metropolitans mosquito menace is a nightmare. Due to extensive human activity and the drainage system, overloaded beyond its capacity with urban sewage that is flowing throughout the year as open canals could be conducive ambiances for mosquito multiplication and thereby promoting the spread of mosquito associated pathogens. The need to protect residents and visitors from the health risk, severe annoyance, and discomfort with mosquitoes is a chronic problem. The primary objective of this study is to suppress the development of larval mosquitoes in urban sewage water thereby reducing mosquito population, while reducing the treat of mosquito born disease transmission, all at the least possible cost, and with the least possible impact on people and the natural environment. Any activity of one species that reduces the adverse effect of another is a biological control, which is a part of natural control and can apply to any type of organism, regardless of whether the bio-control agent occurs naturally, introduced by humans, or manipulated in any way. Therefore the water extract of the leaf of Chloroxylon swietenia was used at different concentrations while keeping in view of it’s traditional usage as a mosquito repellent in rural areas and in the present finding it is found that the extract is proven effective in mosquito larval killing.

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